S-TIER | BUILD MERCENAIRE GRENADES LEVELING – GEMLING LEGIONNAIRE (@GuyThatDies) | SAISON 5

Build Video

Build Overview

This Mercenary Grenades Gemling Legionnaire build is presented by GuyThatDies as the fastest league starter in Path of Exile 2 0.4, capable of reaching maps in 3h38 self-found. It leverages the Mercenary’s full grenade arsenal (Explosive, Gas, Oil, Flash, Cluster) supported by the crossbow and elemental exposure scaling for exceptional clear speed as early as Act 1.

The gameplay relies on a cooldown grenade rotation where each piece has a distinct role: Explosive Grenade for the main DPS, Gas Grenade for sustained area damage (persistent clouds), Oil Grenade to break boss resistances, Flash Grenade to Stun I packs, and Cluster Grenade as the endgame finisher from level 52. The key support Multishot I multiplies all grenades, and Elemental Armament I + Deliberation reinforce their scaling throughout the acts.

The Gemling Legionnaire ascendancy elevates this philosophy: the class scales via the quality of gems themselves, transforming each support upgrade into an immediate DPS gain. The build is designed to be smooth to learn, low dependency on chase gear, and accessible to all player profiles — from PoE2 newcomers to map pushers.

Strengths / Weaknesses

Gem Setup by Stage

This build offers 3 progression stages from leveling to the final build. Select a stage to view the corresponding gem setup.

Level 1-13 Level 14-51 Level 52+

Level 1-13

5 skills • 8 gemmes

Grenade explosiveExplosive Grenade

Grenade assourdissanteFlash Grenade

Attrition

Bombe de givreFrost Bomb

BondissementSet 2

Level 14-51

8 skills • 18 gemmes

Grenade explosiveExplosive Grenade

Grenade assourdissanteFlash Grenade

Grenade suffocanteGas Grenade

Oil Grenade

Attrition

Héraut de la cendreHerald of Ash

Bombe de givreFrost Bomb

BondissementSet 2

Level 52+

8 skills • 23 gemmes

Grenade explosiveExplosive Grenade

Grenade assourdissanteFlash Grenade

Grenade suffocanteGas Grenade

Oil Grenade

Attrition

Héraut de la cendreHerald of Ash

Grenade à fragmentationCluster Grenade

BondissementSet 2

Recommended Equipment

• Main weapon (Set 1): Varnished Crossbow in mid-leveling (around level 5-10), then upgrade to the Bombard Crossbow in the Sandswept Marsh. A crafting guide is provided in the video description to optimize stats.
• Secondary weapon (Set 2): a weapon set dedicated to Pounce in order to keep notable Overwhelm on Set 1 (avoids the attack speed penalty on Pounce).
• Lesser Jewel Orbs: retrieved via the Buried Shrines and the Azak Campfire — to use on Explosive Grenade then Gas Grenade to add Magnified Area (later replaced by Deliberation).
• Greater Jewel Orb: retrieved on the Carnus mechanic in late campaign, to unlock an additional support gem slot.
• Campaign support gems: Multishot I I/II (Ariagny), Elemental Armament I I/II, Deliberation (tier 3 season mechanics), Stun I II (for Flash Grenade), Persistent Ground I I/III (for Oil Grenade), Short Fuse I I + Cooldown Recovery I II (Cluster Grenade endgame).
• Stat priorities: Intelligence first (to unlock Pounce after Crowbell), then Strength and Dexterity. Beyond that, gear dominates — elemental resistances, life, weapon damage.

Gameplay Tips

• Act 1 boss combo (before Gas Grenade): Frost Bomb first → 2 Explosive grenades during its cooldown → Fragmentation Rounds as filler → recast Frost Bomb to stack exposure, then unload.
• Mid-game boss combo (with Gas Grenade): 2 Gas Grenades before the boss becomes damageable, then detonate with Explosive as soon as it is. Then rotate skills off cooldown.
• Endgame boss combo (with Oil Grenade): Oil Grenade first (resistances down) → Gas Grenade → Explosive Grenade. Reapply Oil as soon as it expires.
• Gas Grenade cap: maximum 6 active clouds at once. With Multishot I, 2 throws already hit the cap — no point throwing more before detonating.
• Passive tree pathing: notable Ricochet → notable Overwhelm (Set 1 mandatory) → notable Grenadier → notable Adrenaline Rush → notable Repeating Explosives → notable Demolitionist → notable Crushing Judgement → notable Authority → notable Colossal Weapon.
• Vaal Haste: pick up after the Azak Vaag boss, gives a big clear speed boost.
• Pounce on Set 2: lets you keep notable Overwhelm active on the main weapon without penalizing Pounce’s attack speed, and to cross some campaign obstacles.
• Drop Frost Bomb at level 20: the skill stops working against higher-level enemies, frees a slot for Gas Grenade or another.
• Ferocious Roar (optional, level 22): +30% damage at max rage, but makes gameplay clunky. Reserve for players min-maxing DPS.

The Boss Combo: from Frost Bomb to Oil Grenade

The strength of the build lies in the evolution of its boss combo throughout the campaign. Early Act 1, without Gas Grenade, the player relies on Frost Bomb to stack Cold Exposure: drop the bomb, throw two Explosive Grenades during its cooldown, and recast as soon as it returns. This is enough for early bosses and lets you learn the rotation smoothly.

From level 5, the arrival of Gas Grenade changes everything. The combo becomes: 2 Gas Grenades during the boss invulnerability phase, then explosive detonation as soon as it becomes targetable. The persistent clouds deal continuous damage and allow chaining rotations without downtime.

The endgame introduces Oil Grenade in the Sandswept Marsh, which becomes the first link of the combo as it reduces enemy resistances and scales ignite damage. The final sequence — Oil → Gas → Explosive (+ Frost Bomb if still active) — becomes the build’s max DPS before the arrival of Cluster Grenade at level 52.

Cluster Grenade and the Level 52 Power Spike

Level 52 marks the arrival of the build’s final skill: Cluster Grenade. This grenade that fragments into several sub-grenades becomes the pack finisher and a formidable complement to the boss combo. Supported by Multishot I II, Cooldown Recovery I II, Short Fuse I I and Deliberation, it composes a damage cannon that transforms the Flow of play.

The author specifies that Deliberation can be replaced by Fire Judgment if the build only uses physical and fire damage, for a small extra damage gain. The Greater Jewel Orb obtained via the Carnus mechanic adds an extra support gem slot to Cluster Grenade, unlocking its maximum potential.

From this point, the build « scales by itself »: gems upgrade in quality (the Gemling Legionnaire’s strong point), the crossbow gains tiers, and equipment looted in maps takes over progression.

Passive Tree Progression: from Ricochet to Authority

The passive tree follows an arc trajectory covering the pillars of the build: projectiles, grenades, exposure and weapon power. The start heads toward notable Ricochet (projectile rebound, useful for fragmentation rounds), then quickly shifts to notable Overwhelm to increase the grenades’ armor break.

Act 2, the player continues with notable Colossal Weapon (raw crossbow power), notable Grenadier (cluster of grenade-dedicated improvements), then notable Adrenaline Rush and notable Repeating Explosives for a direct DPS and rate-of-fire boost to Cadence.

Act 3 and beyond, you pick up notable Demolitionist, notable Crushing Judgement and notable Authority. These nodes finish scaling grenades in damage and utility. The order matters: notable Overwhelm MUST be allocated on weapon Set 1, in order not to penalize Pounce’s attack speed on Set 2.

The Gemling Legionnaire: Why This Ascendancy?

The Gemling Legionnaire ascendancy is one of the three Mercenary ascendancy choices and the one that elevates this grenade build. Its main mechanic relies on scaling via gem quality: every support gem upgrade (Multishot I I → II, Elemental Armament I I → II, Deliberation) translates into direct DPS gain, without needing to modify the passive tree or equipment.

This philosophy explains why the build relies so heavily on jewel orbs (Lesser and Greater) picked up via season mechanics. Each slot added to a grenade multiplies its potential. It is also an ascendancy that forgives suboptimal gear choices early in the campaign: as long as the gems are at the right tier, DPS stays competitive.

The result is a smooth and readable build, where visible progression comes from every support gem upgrade pickup rather than from each unique chase drop. Ideal for a league starter.

The Final Tip: Gear Dominates the Build

GuyThatDies concludes the video on a philosophical point important for PoE2: equipment matters more than the build choice. Good gear can triple or quadruple a build’s damage, meaning a player running a « weaker » build with excellent gear often outperforms a player running the « best build » of the moment with mediocre gear.

Concretely, after the campaign ends, the priority is no longer to spam passive tree points or to micro-optimize the rotation: you have to invest in the crossbow, rings, amulet and resistances. The Grenades Gemling Legionnaire build potential is such that it easily handles « gear acquisition » phases without changing its gems.

For more details, the author references a complete « 1 to Maps » guide and a video dedicated to mobile loot in the description — check those out to structure your endgame progression.

Skill Tree